<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Flex 弹性盒子</title>

    <style>
        html {
            font-size: 10px;
        }

        .container {
            display: flex;
            height: 40rem;
            background-color: aquamarine;
            /* flex-direction: column-reverse; */
            /* flex-wrap: wrap; */
            /* justify-content: space-around; */
            /* align-items: center; */
            align-content: center;
        }

        .box {
            width: 20rem;
            font-size: 8rem;
        }
    </style>
</head>
<body>
    <div class="container">
        <div class="box" style="background-color: green;">1</div>
        <div class="box" style="background-color: red;">2</div>
        <div class="box" style="background-color: gray;">3</div>
        <div class="box" style="background-color: yellow;">4</div>
        <div class="box" style="background-color: brown;">5</div>
        <div class="box" style="background-color: #4aa;">6</div>
    </div>
</body>
</html>